Production and processing of subject-verb agreement in monolingual Dutch children with specific language impairment.

PURPOSE In this study, the authors investigated whether errors with subject-verb agreement in monolingual Dutch children with specific language impairment (SLI) are influenced by verb phonology. In addition, the productive and receptive abilities of Dutch acquiring children with SLI regarding agreement inflection were compared. METHOD An SLI group (6-8 years old), an age-matched group with typical development, and a language-matched, younger, typically developing (TD) group participated in the study. Using an elicitation task, the authors tested use of third person singular inflection after verbs that ended in obstruents (plosive, fricative) or nonobstruents (sonorant). The authors used a self-paced listening task to test sensitivity to subject-verb agreement violations. RESULTS Omission was more frequent after obstruents than nonobstruents; the younger TD group used inflection less often after plosives than fricatives, unlike the SLI group. The SLI group did not detect subject-verb agreement violations if the ungrammatical structure contained a frequent error (omission), but if the ungrammatical structure contained an infrequent error (substitution), subject-verb agreement violations were noticed. CONCLUSIONS The use of agreement inflection by children with TD or SLI is affected by verb phonology. Differential effects in the 2 groups are consistent with a delayed development in Dutch SLI. Parallels between productive and receptive abilities point to weak lexical agreement inflection representations in Dutch SLI.